Optical navigation systems operate to estimate movements between the optical navigation systems and target surfaces to perform tracking operations. An optical navigation system uses a light source, such as a light-emitting diode (LED) or a laser diode, to illuminate a region of a target surface and an image sensor to receive the light reflected from the target surface to successively capture frames of image data of the target surface. The optical navigation system compares the successive image frames and estimates the relative movements between the optical navigation system and the target surface based on the comparison between the current image frame and a previous image frame. The comparison is based on detecting and computing displacements of features in the captured frames of image data.
Optical navigation systems are commonly used in optical computer mice to track the movements of the mice relative to the navigation surfaces on which the mice are manually manipulated. The movements of a computer mouse are used to control a cursor on a monitor of a computer system. The accuracy of an optical computer mouse with respect to the positioning of the cursor depends on the quality of image frames of a navigation surface that are captured for image comparisons.
A concern with a conventional optical computer mouse is that contamination of dust and/or other material on the optical elements of the mouse introduces a spatial noise pattern in the captured image frames of the navigation surface. These image frames with optical spatial noise pattern can lead to displacement calculation errors, which may degrade the tracking performance of the optical computer mouse. Another concern is that intensity variations in the captured frames of image data due to manufacturing deviations in the image sensor and/or other electrical components of the optical navigation system may also degrade the tracking performance of the optical computer mouse.
In view of these concerns, there is a need for a system and method to address the spatial noise pattern due to optical and electrical sources in the frames of image data that are used for displacement estimation.